Malignant hyperthermia clinical features

1. earliest possible sign: increase in end-tidal pCO2

2. tachycardia (early) and other arrhythmias

3. with progression:

a) coagulation disorder (DIC) (bleeding from surgical wound and body orifices)

b) ABG: increasing metabolic acidosis & decreasing pO2

c) pulmonary edema

d) elevated body temperature (may reach ≥ 44 °C (113 °F) at rate of 1 °C/5‑min) (normal patients become hypothermic with general anesthesia)

e) limb muscle rigidity (common, but late)

f) rhabdomyolysis → elevated CPK & myoglobin (late)

4. terminal:

a) hypotension

b) bradycardia

c) cardiac arrest

Classical manifestations comprise of tachycardia, increase in expired carbon dioxide levels, muscle rigidity, hyperthermia (>38.8°C) and unexpected acidosis ¹⁾.